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Full-Text Articles in Physics
Ice Nucleation At The Contact Line Triggered By Transient Electrowetting Fields, Fan Yang, Raymond Shaw, Colin Gurganus, Su Kong Chong, Yoke Khin Yap
Ice Nucleation At The Contact Line Triggered By Transient Electrowetting Fields, Fan Yang, Raymond Shaw, Colin Gurganus, Su Kong Chong, Yoke Khin Yap
Department of Physics Publications
Supercooled water is found to have a significantly enhanced freezing temperature during transient electrowetting with electric fields of order 1 V/μm. High speed imaging reveals that the nucleation occurs randomly at the three-phase contact line (droplet perimeter) and can occur at multiple points during one freezing event. Possible nucleation mechanisms are explored by testing various substrate geometries and materials. Results demonstrate that electric field alone has no detectable effect on ice nucleation, but the moving boundary of the droplet on the substrate due to electrowetting is associated with the triggering of nucleation at a much higher temperature.
Switching Behaviors Of Graphene-Boron Nitride Nanotube Heterojunctions, Vyom Parashar, Corentin Durand, Boyi Hao, Rodrigo Amorim, Ravindra Pandey, Bishnu Tiwari, Dongyan Zhang, Yang Liu, An-Ping Li, Yoke Khin Yap
Switching Behaviors Of Graphene-Boron Nitride Nanotube Heterojunctions, Vyom Parashar, Corentin Durand, Boyi Hao, Rodrigo Amorim, Ravindra Pandey, Bishnu Tiwari, Dongyan Zhang, Yang Liu, An-Ping Li, Yoke Khin Yap
Department of Physics Publications
High electron mobility of graphene has enabled their application in high-frequency analogue devices but their gapless nature has hindered their use in digital switches. In contrast, the structural analogous, h-BN sheets and BN nanotubes (BNNTs) are wide band gap insulators. Here we show that the growth of electrically insulating BNNTs on graphene can enable the use of graphene as effective digital switches. These graphene-BNNT heterojunctions were characterized at room temperature by four-probe scanning tunneling microscopy (4-probe STM) under real-time monitoring of scanning electron microscopy (SEM). A switching ratio as high as 105 at a turn-on voltage as low …
Disdrometer Network Observations Of Finescale Spatial–Temporal Clustering In Rain, A. R. Jameson, M. L. Larsen, A. Kostinski
Disdrometer Network Observations Of Finescale Spatial–Temporal Clustering In Rain, A. R. Jameson, M. L. Larsen, A. Kostinski
Department of Physics Publications
The spatial clustering of drops is a defining characteristic of rain on all scales from centimeters to kilometers. It is the physical basis for much of the observed variability in rain. The authors report here on the temporal–spatial 1-min counts using a network of 21 optical disdrometers over a small area near Charleston, South Carolina. These observations reveal significant differences between spatial and temporal structures (i.e., clustering) for different sizes of drops, which suggest that temporal observations of clustering cannot be used to infer spatial clustering simply using by an advection velocity as has been done in past studies. It …
On The Variability Of Drop Size Distributions Over Areas, A. R. Jameson, M. L. Larsen, A. B. Kostinski
On The Variability Of Drop Size Distributions Over Areas, A. R. Jameson, M. L. Larsen, A. B. Kostinski
Department of Physics Publications
Past studies of the variability of drop size distributions (DSDs) have used moments of the distribution such as the mass-weighted mean drop size as proxies for the entire size distribution. In this study, however, the authors separate the total number of drops Nt from the DSD leaving the probability size distributions (PSDs); that is, DSD = Nt × PSD. The variability of the PSDs are then considered using the frequencies of size [P(D)] values at each different drop diameter P(PD | D) over an ensemble of observations collected using a …
Recent Advancement On The Optical Properties Of Two-Dimensional Molybdenum Disulfide (Mos2) Thin Films, Mingxiao Ye, Dustin Winslow, Dongyan Zhang, Ravindra Pandey, Yoke Khin Yap
Recent Advancement On The Optical Properties Of Two-Dimensional Molybdenum Disulfide (Mos2) Thin Films, Mingxiao Ye, Dustin Winslow, Dongyan Zhang, Ravindra Pandey, Yoke Khin Yap
Department of Physics Publications
The emergence of two-dimensional (2D) materials has led to tremendous interest in the study of graphene and a series of mono- and few-layered transition metal dichalcogenides (TMDCs). Among these TMDCs, the study of molybdenum disulfide (MoS2) has gained increasing attention due to its promising optical, electronic, and optoelectronic properties. Of particular interest is the indirect to direct band-gap transition from bulk and few-layered structures to mono-layered MoS2, respectively. In this review, the study of these properties is summarized. The use of Raman and Photoluminescence (PL) spectroscopy of MoS2 has become a reliable technique for differentiating …